Draw the following 2-pentene 5,6-dimethyloct-3-en-1-yne 2,3,3-trimethylbut-1-ene 2-chloro-2-methylpropane If done correctly, they should match some of the odd numbers on the HW packet

Check your evens Alkene 2. Prop-1-ene 4. 3-sec-butyl-2-methylhept-2-ene 6. Hex-3-ene 8. 4-methylpent-2-ene 10. 5-ethyl-4,6-dimethyloct-2-ene 4. Hept-3-ene Alkyne 2. but-2-yne 4. non-4-yne 6. 5-ethyl-5-methyloct-3-yne 8. pent-3-en-1-yne 10. hept-3-en-1-yne

Check your odds Alkene 1. ethene 3. pent-2-ene 5. 3-sec-butyl-2-methylhept-2-ene 7. 5-isopropyloct-3-ene 9. 2,3,3-trimethylbut-1-ene 3. 1-butene 5. 4-methylhex-2-ene Alkyne 1. but-1-yne 3. prop-1-yne 5. 5,5-dimethylhex-1-yne 7. 3-methyl-oct-1,4-diyne 9. oct-5-en-2-yne 11. 5,6-dimethyloct-3-en-1-yne

Cycloalkanes Cyclopropane C3H6 Draw #6 1-ethyl-2,5-dimethylcycloheptane #8, 3, 13

Learning Check Write the IUPAC name for each of the following unsaturated compounds: A. CH3CH2CCCH3 CH3 B. CH3C=CHCH3 C.

Aromatic Compounds and the Structure of Benzene In the early days the word aromatics was used to described many fragrant molecules isolated from natural sources. Today the term aromatic is used to describe benzene like molecules. Benzene is a flat, symmetrical molecule with the molecular formula C6H6. It has alternating three carbon-carbon double and three single bonds.

Aromatic Compounds and Benzene Aromatic compounds contain benzene. Benzene, C6H6 , is represented as a six carbon ring with 3 double bonds. Two possible can be drawn to show benzene in this form.

Benzene’s relatively lack of chemical reactivity is due to its structure. There are two possible structures with alternating double and single bonds.

The properties of benzene can only be explained by assuming that the actual structure of benzene is an average of the above two possible equivalent structures-known as resonance. Simple aromatic compounds like benzene are non-polar, insoluble in water, volatile, and flammable.

Aromatic Compounds in Nature and Health Many aromatic compounds are common in nature and in medicine.

Naming Aromatic Compounds Aromatic compounds are named with benzene as the parent chain. One side group is named in front of the name benzene. - No number is needed for mono-substituted benzene since all the ring positions are identical. methylbenzene chlorobenzene (toluene)

Naming Aromatic Compounds When two groups are attached to benzene, the ring is numbered to give the lower numbers to the side groups. The prefixes ortho (1,2), meta (1,3-) and para (1,4-) are also used.

Some Common Names Some substituted benzene rings also use a common name. Then naming with additional more side groups uses the ortho-, meta-, para- system.

Many substituted aromatic compounds have common names in addition to their systematic names.

Learning Check Select the names for each structure: a. Chlorocyclohexane b. Chlorobenzene c. 1-chlorobenzene a. Meta-xylene b. Meta-dimethylbenzene c. 1,3-dimethylbenzene

Learning Check Write the structural formulas for each of the following: A. 1,3-dichlorobenzene B. Ortho-chlorotoluene OR 2-chlorotoluene

Functional Group Ending alkane ane alkene ene alkyne yne alcohol ol ketone one aldehyde al carboxylic acid oic acid ester oate amide